High frequency luminescent sign



Aug. 25, 1959 s. CUKER HIGH FREQUENCY LUMINESCENT SIGN Filed Feb. 9, 1956 F IG. 5

INVENToR SEYMOUR CUKER f@ M ATTORNEY FIG.1

nited States Patent HIGH FREQUENCY LUMINESCENT SIGN Seymour Cuker, Whitestone, N.Y., assignor, by mesne assignments, to Jacqueline Modes, Inc., New York, N.Y., a corporation Application February 9, 1956, Serial No. 564,459

9 Claims. (Cl. 315-248) This invention relates to illuminated electrical signs, and more speciiically concerns signs utilizing individual electrical discharge tubes containing sealed-in ionizable gases.

It has been proposed to provide illuminated signs made up of individual, movable characters derived from sealed discharge tubes and placed Within the iniiuence of a high frequency field generated by a suitable oscillator. However, such signs of known construction present a number of problems in use.

Thus, the potential gradient necessary to initially excite the gases in the discharge tubes is considerably greater than the potential gradient required to maintain the tubes at proper luminosity after the initial starting period. However, with known devices, the maximum starting potential is continued after the initial starting period, with a consequent diminution in the effective life of the individual discharge tubes, as well as a decrease in overall operating efficiency of the sign.

Accordingly, an object of this invention is to provide an improved frequency luminescent sign using individual characters or letters in the form of electrical discharge tubes, wherein -a relatively high potential gradient is used to initiate the excitation of the gases in the tubes and a relatively low potential gradient is used to maintain the luminosity of the tubes during the operating periods thereof.

Another object of this invention is to provide in a sign of the character described, an electrode system arranged to produce a pair `of high frequency fields in a determined space relationship, one of the fields being of a relatively high potential gradient, the other field being of a relatively low potential gradient; the individual discharge tubes being disposed in relation to such lields so that the tubulations or stem portions of said tubes are intimately related to and under the direct influence of the high iield strength for initiating the excitation of the gases in lsaid tubes, the tubes as a whole being exposed to the low field strength for maintaining the luminosity of the tubes during the operating periods thereof.

A further object of this invention is to provide in a sign of the character described, an electrode system arranged to produce a pair of high frequency iields in space quadrature relationship, one of the fields being at `a relatively high potential gradient and being directly applicable to a restricted portion of the individual gas discharge tubes to initially excite the gases therein, the other of the fields being of a relatively low potential gradient and being applicable to a major portion of said tubes to maintain the luminosity thereof during their operating periods.

Still another object `of this invention is to provide a luminescent high frequency sign wherein the electrode system is of a character and disposition such as to leave a maximum amount of the surface area of the individual discharge tubes freely visible unobscured as viewed ,from either side of the sign.

Still a further object of this invention is to provide an improved electrode system for luminescent signs, wherein the electrodes are arranged in a manner to materially reduce undesirable radiation effects for a given field strength derived from the electrodes and of a magnitude to properly excite the discharge tubes.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

In the drawing,

Fig. l is an elevational view of a high frequency luminescent sign embodying the invention, with parts broken away;

Fig. 2 is a sectional view taken on the line 2-2 of Fig. l;

Fig. 2A is an enlarged sectional view taken on the line ZA-ZA of Fig. l;

Fig. 3 is a digrammatic showing of the connections between the electrodes of the sign and a high frequency source;

Fig. 4 is a partial elevational view of a sign having a modiiied form `of electrode arrangement;

Fig. 5 is a partial elevational view of .a sign having -a modified form of electrode and discharge tube support;

Fig. 6 is a vertical transverse sectional view thereof.

Referring in detail to the drawing, and particularly to Fig. l, 10 designates a high frequency sign embodying the invention. The same comprises supporting means generally indicated at 11, on which individu-al characters such as lettersl 12, 13 may be larranged as desired. Each character is formed from sealed glass tubing containing ionizable gases at reduced pressure; such characters being adapted to become luminescent upon being subjected to the inuence of a high frequency electrical field.

The supporting means 11 comprises a at base member 14 of a length suited to the maximum number of characters 12, 13 to be arranged thereon; with uprights 15, 16 at the opposite ends thereof. Support means 11 may be formed of wood, plastic or other suitable dielectric material.

The base 14 is formed with Ia centrally located, longitudinally extending narrow, shallow groove or channel 17, for receiving and locating the lower ends of' characters 12, 13. In forming such characters, a tubulation or stem 18 extends from `the lower ends thereof, the same being hollow and communicating with the interior of the glass tubing Iof the character. The stem 18 is embedded in a footing or base 19 formed of plastic or the like, such base having a transverse section complementaryto that of channel 17, thus allowing suitable placement and movement of characters 12, 13 on support 11.

A single, elongated electrode 20, of relatively small cross section, is mounted between uprights 15, 16 adjacent the upper ends thereof. Electrode 2l) acts las a support for the characters 12, 13 as they are 'vertically positioned on base 14, the upper portions of the characters resting against said electrode. The major portion of said characters is exposed to view and the same may be clearly seen from either side of the sign.

A pair of elongated electrodes 21, 22 are embedded in the base member 14, being respectively located on either side of channel 17 therein, and in close proximity to the walls of said channel, and therefore, closely -related to the stems 18 of characters 12, 13. The electrodes 21, 22 may be disposed in a substantially common horizontal plane, while electrodes 20, 21 may be disposed in a substantially common vertical plane.

Electrodes 20, 22 are interconnected by a conductor 23, the thus* interconnected electrodes and remaining electrode 21 being connected to a receptacle 24 on upright 15. A plug 25, receivable in receptacle is connected to one end of a cable 26, which.` is connected at -the other end -tofa With the arrangement of electrodes 20, 21 and 22, as i shown and described, it may be said that there is provided one high frequency field defined by electrodes 2t), 21 which is in space quadrature relation to a second high frequency field defined by electrodes 21, 22. Furthermore, with the close capacitive coupling of electrodes 21, 22, a substantially high potential gradient is applied to the stems 18 of characters 12, 13 to excite the ionizable gases therein and to initiate the luminescence thereof; the high potential being conned to such stems and not extending to any material surface portions of the body of characters 12, 13.

It will also be apparent, that for a given output of source 27, the relatively high potential gradient between electrodes 21, 22 is in contrast with the much lower potential gradient between electrodes 20, 21 which have a substantial spacing therebetween. It follows that the discharge tubes forming the various characters 12, 13, with their major surface areas under the influence of a relatively low potential gradient, will exhibit a substantially increased useful life.

It has been found that the operating eiciency of the device is materially increased with a reduction in the cross section of the several electrodes and with a minimum use of `dielectric material in association with such electrodes. Thus, electrodes 21, 22 are bridged by a relatively small amount of dielectric material.

With but a single electrode exposed to view on support 11, such electrode having a minimum surface area in contact with characters 12, 13 and the electrode preferably being covered with a black dielectric jacket or film, i

maximum visibility -of the illuminated characters is obtained, with a clear view thereof from either side of the sign. The dielectric jacket provi-des safety means in the event of accidental contact with the electrode 20, as well as means for reducing the visibility of said electrode. Furthermore, it has been found that with the use of the closely spaced electrodes 21, 22, for a given eld strength produced thereby, radiation effects are substantially reduced.

If desired, as shown in Fig. 4, another electrode 2S may be mounted between uprights 15, 16, below electrode 20 and coplanar therewith, as a means for more effectively exciting the cross strokes or intermediate portions of characters 12, 13. Electrode 28 may be connected to electrode 20 through conductor 23.

As shown in Fig. 5, the supporting means 11a may comprise the elongated dat base 14a and an elongated panel 30 upstanding from a central portion of said base; the channel or groove 17a being formed in the base adjacent the lower end of panel 30. Electrodes 21, 22 are embedded in base 14a on either side of channel 17a, as previously described, while electrode 20 is embedded in an upper portion of panel 30. Such supporting means may be molded or otherwise formed from laminated dielectric materials, the electrodes being suitably located therein. In this case, the rear portions of characters 12, 13 will be in contact with the outer surface portions of panel 30, the Ifootings 19 thereof being receivable and movable in channel 17a.

While, the electrodes 20, 21 and 22 are shown as being disposed in planes at right angles to each other, kthe electrodes may be located so as to provide high frequency fields of high and low potential gradients Which have other angular relationships. However, in all cases, the

As shown in Fig. l, the footings or bases 19 of characters 12, 13 are preferably of a longitudinal extent such as tto project at their opposite ends slightly beyond the extreme lateral projections o-f any character, thereby avoiding glass to glass contact between adjacent characters mounted on support 11 or 11a.

It will thus be seen that there has been provided an improved high frequency luminescent sign in which the several objects of the invention are achieved and which is well adapted to meet the conditions of practical use.

As various changes might be made in the embodiments of the invention herein set forth without departing from the spirit thereof, it is understood that all matter herein shown or described shall be deemed illustrative and not by way of limitation except as set forth in the appended claims.

Having thus disclosed my invention, I claim as new and desire to protect by Letters Patent:

l. A high frequency luminescent 'display sign having individual, gaseous discharge tubes, comprising means for supporting said tubes in an upright position, said means including a base member formed with a longitudinal channel for receiving therein stem portions of said tubes, a pair of longitudinally extending, closely spaced electrodes respectively located on either side of said channel, a third electrode on said support means remotely spaced from one of said pair of electrodes and in a common plane therewith which is disposed at an angle to a common plane including said pair of electrodes.

2. A high frequency sign having individual gaseous discharge tubes vhaving projecting stem portions, supportl means for holding said tubes in a predetermined position, a pair of closely spaced electrodes on said support means disposed in close proximity to said stem portions, a third electrode on said support means for contacting a portion of said tubes remote from the stern portions thereof, and a source of high frequency currents connected to said electrodes to provide `a high electrical field lbetween said pair of electrodes and a low electrical field between said third electrode and one of said pair of electrodes. i

3. Means for exciting a gaseous discharge tube having a stem portion extending therefrom, said means com# prising a pair of closely spaced coplanar electrodes receiving said stem portion therebetween, a third electrodev coplanar with one of said pair of velectrodes for contacting portions of said tube remote from the stem portion thereof, the plane of said pair of electrodes and the plane including said third electrode being in space'quadrature relation to each other, and a source of high frequency current connected to said electrodes.

4. A high frequency luminescent sign having individual, gaseous discharge tubes, said tubes including st em i portions projecting therefrom, means for supporting stems or tubulations 18 extending lfrom characters 12, 13

said tubes comprising an elongated base member formed with a longitudinal channel, footing means for receiving said stem portions in embedded relation thereto, said footing means being slidably mounted in the channel in said base member, a pair of longitudinally extending, closely spaced electrodes mounted in said base and located respectively on either side of the channel therein, a third longitudinally extending electrode on said supporting means and contacting portions of said tubes remote from the stem portions thereof, said pair of electrodes being operative upon application thereto of high frequency electrical current to provide a high electrical field to the stem portions of said tubes, said third electrode and one of said pair of electrodes being operative upon the application thereto of high frequency electric current to provide a lowV electrical eld to extended portions of said tubes.

5.v A luminescent sign as in claim 4 wherein said sup.- porting means comprises panel means upstanding from said base member, said third electrode being embedded in said panel means adjacent one surface thereof.

6. A high lfrequency luminescent sign having individual, gaseous discharge tubes, said tubes including stem portions depending from lower portions of said tubes, means for supporting a plurality of said tubes in predetermined arrangement, said means comprising a base member formed with a longitudinal channel of restricted Width for receiving the stem portions of said tubes, a pair of closely spaced, longitudinally extending electrodes on said base member and located respectively on either side of said channel, a third electrode, means for mounting said third electrode in vertically spaced relation to said pair of electrodes and in a plane including one of said pair of electrodes, circuit means connecting said third electrode and one of said pair of electrodes, said pair of electrodes being operative upon the application thereto of a high frequency current to provide a high electrical field, said third electrode and the electrode interconnected therewith being operative upon the application thereto of a high frequency current to provide a low electrical field.

7. A sign as in claim 6 wherein said second mentioned means comprises longitudinally spaced members upstanding from said base member for suspending said third electrode therebetween, said third lelectrode being adjacent portions of said tubes remote from the stem portions thereof.

8. A sign as in claim 7 wherein said third electrode includes a dark dielectric covering on the surface thereof.

49. A sign as in claim 6 and further including a fourth electrode located intermediate said third elect-rode and said pair of electrodes, said fourth electrode being coplanar with said third electrode and circuit means con necting said third and fourth electrodes.

References Cited in the iile of this patent UNITED STATES PATENTS 2,142,633 Dey Jan. 3, 1939 2,181,889 Hanson Dec. 5, 1939 2,322,008 Fodor June 15, 1943 2,362,157 Quill NOV. 7, 1944 2,488,169 Browner Nov. 15, 1949 

